1. Field
The present invention relates to a chip-type electric double layer capacitor and a method of manufacturing the same, and more particularly, to a chip-type electric double layer capacitor which may be reduced in size and weight and a method of manufacturing the same.
2. Description of the Related Art
In various electronic products such as information communication devices, a stable energy supply is considered to be an important element. In general, such a function is performed by a capacitor. That is, the capacitor serves to store electricity in a circuit provided in various electronic products such as information communication devices and then discharge the electricity, thereby stabilizing the flow of electricity with the circuit. A general capacitor has a short charge and discharge time, a long lifespan, and high output density. However, since the general capacitor has low energy density, there is a limitation in using the capacitor as a storage device.
To overcome such a limitation, a new category of capacitors such as electric double layer capacitors have recently been developed, which have a short charge and discharge time and high output density. A great deal of attention is being paid to such capacitors as next generation energy devices together with secondary cells.
The electric double layer capacitor is an energy storage device using a pair of charge layers (electrode layers) having a different polarity. The electric double layer capacitor may perform continuous electrical charge and discharge cycles and has higher energy efficiency and output and greater durability and stability than other, more general capacitors. Accordingly, the electric double layer capacitor which may be charged and discharged with high current is being recognized as a storage device which may be charged and discharged at a high frequency, such as an auxiliary power supply for mobile phones, an auxiliary power supply for electric vehicles, and an auxiliary power supply for solar cells.
A basic structure of the electric double layer capacitor includes an electrode, an electrolyte, a current collector, and a separator. The electrode has a relatively large surface area such as a porous electrode. The operational principle of the electric double layer capacitor is an electro-chemical mechanism in which electricity is generated when a voltage of several volts is applied to both ends of a unit cell electrode such that ions in the electrolyte move along an electric field to be adsorbed by an electrode surface.
In general, to surface mount such an electric double layer capacitor on a circuit board, a bracket is welded over and under the electric double layer capacitor, and the electric double layer capacitor is then mounted on the circuit board through the bracket.
However, the electric double layer capacitor having such a structure has a relatively large thickness. Due to the additional structures required for surface mounting, such as the brackets and so on, the thickness further increases. When such an electric double layer capacitor is used, there may be difficulties in manufacturing high-capacity products because of the increase in thickness. Furthermore, since an additional manufacturing process must be performed, the price of products inevitably increases.